He went on to say that the personality traits he looks for the most in traders and analysts are openness to change and grit (or resilience).

"I would argue that the single most important thing you could do as an organization is hire the right people," Frederick Morgeson, an organizational psychology expert and professor of management at Michigan State University, tells Business Insider.

And a key way to do that, he argues, is by investing time, energy, and money into properly conducting personality assessments.

Morgeson says what's truly unique and commendable about Karp's tactic is his clear understanding of what he needs for the job and the company. This is the crucial first step to conducting personality assessments the right way.

Why do personality assessments matter?

The point of personality assessments, Morgeson says, is to get an idea of what traits someone possesses and what types of behaviors they engage in so you can assess how well they match up to the traits you believe are really important for success in the job and in the organization.

Questions like, "To what extent do you like trying new or different things?" and, "Tell me about a time when you had to try something new," for example, would indicate a job candidate's level of openness to new experiences and change.

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Morgeson points out that if a company hires someone who makes between $50,000 and $60,000 a year, over the course of a 20-year career, that's at least a million-dollar investment in that person.

According to Tomas Chamorro-Premuzic, a professor of business psychology at University College London and Columbia University and CEO of personality profiling company Hogan Assessment Systems, when tests are scientifically validated, they are better at predicting future performance than interviews, references, and résumés.

Here are the steps you need to take to get the most out of your own company's personality assessments:

1. Understand your needs.

The first step to personality assessments is figuring out your company's values, missions, and the needs for the job.

"If you don't do the work as an organization to make sure that those traits that you're trying to find in your candidates are in fact the right traits for your organization and for the jobs they're doing, you're going to have problems," Morgeson says.

Businesses need to ask:

What is is going to take to be successful in the job?

What is it going to take to be successful in the organization?

Only once these ideal traits are clear can a business proceed to the next step of assessing candidates' personalities and their fit.

2. Pick an assessment.

Karp said his company looks for openness to change, which is one of the "Big Five" personality traits, another common model for assessing potential new hires.

Collectively, these traits are often referred to with the acronym OCEAN, which stands for openness, conscientiousness, extraversion, agreeableness, and neuroticism. Even though Karp said that neuroticism could lead to what he calls a "nuisance hire" — someone that has potential, but could be a drain on the company — he admitted that he himself exhibits this trait.

Often people will exhibit a mixture of some of these personality traits, Morgeson says, but there are usually a few that stand out to assessors more than others.

3. Beware of common mistakes.

Where companies often trip up, Morgeson explains, is not assessing these personality traits the right way.

"One of the things that the field [of organizational psychology] has struggled with is, we know these personality traits matter for how people perform, but how do we get at them, how do we measure them, how do we effectively assess them?"

Assessors could potentially ask the wrong kinds of questions to discern a personality trait.

"Even though they have an idea of what they want, they're not engaging in a process that will really help them understand the candidates' or the applicants' standing on those characteristics," he says.

Critics of personality assessments also claim it's too easy to game these tests. John Rust, director of Cambridge University's Psychometrics Centre, told the economist that because the expected answers to these assessments are often clear, companies wind up "selecting the people who know what the right answers are."

Morgeson admits this is especially problematic when using these assessments for hiring, since job applicants are more motivated to lie and tell interviewers what they want to hear. But good personality assessors have ways to know when someone's lying, he says:

They build a lie/cheat scale into the assessment. One way to do this is to ask a candidate if they endorse something that doesn't exist. If they answer in the affirmative, this raises the question, what else are they lying about?

When a potential hire's answers seem too good to be true, they follow up with them about it in some kind of interview process.

They reach out to the candidate's references and ask them to answer the same question about the job candidate and see if the responses line up.

"The whole point of the hiring process is you're trying to learn the most you can about an applicant in as many different ways as possible," Morgeson says.